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1ump
From Proteopedia
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==Overview== | ==Overview== | ||
| - | The membrane protein squalene-hopene cyclase was cocrystallized with | + | The membrane protein squalene-hopene cyclase was cocrystallized with 2-azasqualene and analyzed by X-ray diffraction to 2.13 A resolution. The conformation of this close analog was clearly established, and it agreed with the common textbook presentation. The bound squalene undergoes only small conformational changes during the formation of rings A through D, thus requiring no intermediate. However, ring E formation is hindered by an entropic barrier, which may explain its absence in the steroids. The structure analysis revealed a mobile region between the active center cavity and the membrane, which may melt, opening a passage for squalene and hopene. |
==About this Structure== | ==About this Structure== | ||
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[[Category: Squalene--hopene cyclase]] | [[Category: Squalene--hopene cyclase]] | ||
[[Category: Balliano, G.]] | [[Category: Balliano, G.]] | ||
| - | [[Category: Reinert, D | + | [[Category: Reinert, D J.]] |
| - | [[Category: Schulz, G | + | [[Category: Schulz, G E.]] |
[[Category: C8E]] | [[Category: C8E]] | ||
[[Category: SQA]] | [[Category: SQA]] | ||
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[[Category: triterpene cyclase]] | [[Category: triterpene cyclase]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 15:26:09 2008'' |
Revision as of 13:26, 21 February 2008
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GEOMETRY OF TRITERPENE CONVERSION TO PENTACARBOCYCLIC HOPENE
Overview
The membrane protein squalene-hopene cyclase was cocrystallized with 2-azasqualene and analyzed by X-ray diffraction to 2.13 A resolution. The conformation of this close analog was clearly established, and it agreed with the common textbook presentation. The bound squalene undergoes only small conformational changes during the formation of rings A through D, thus requiring no intermediate. However, ring E formation is hindered by an entropic barrier, which may explain its absence in the steroids. The structure analysis revealed a mobile region between the active center cavity and the membrane, which may melt, opening a passage for squalene and hopene.
About this Structure
1UMP is a Single protein structure of sequence from Alicyclobacillus acidocaldarius with and as ligands. Active as Squalene--hopene cyclase, with EC number 5.4.99.17 Known structural/functional Site: . Full crystallographic information is available from OCA.
Reference
Conversion of squalene to the pentacarbocyclic hopene., Reinert DJ, Balliano G, Schulz GE, Chem Biol. 2004 Jan;11(1):121-6. PMID:15113001
Page seeded by OCA on Thu Feb 21 15:26:09 2008
